Field of Invention
The invention relates to a glider for electric power production from wind. The invention further relates to a system for electric power production from wind.
Brief Description of Related Art
The production of electric power from wind is generally accomplished by airfoils or structures with an aerodynamic profile, which produce lift forces upon exposure to wind. Thereby, energy is extracted from the wind, which can be converted into electricity, for example by exploring said lift forces to drive an electrical generator. Well known wind turbines for instance comprise a rotor with aerodynamically profiled rotor blades, wherein the lift forces of the rotor blades cause the rotor to turn. The rotor is mounted to an electrical generator, which is for example located on top of a tower, for production of electricity.
In order to explore wind energy resources at altitudes above a few hundred meters over ground, where the average wind is stronger and steadier due to less disturbing interaction with the earth's surface, it has been proposed to use airborne airfoils. These concepts are often referred to as airborne wind energy or airborne wind energy production.
One of the challenges of airborne wind energy production is the transferal of energy extracted from the wind at high altitudes to the ground. Two general approaches are proposed, the first providing for an airborne generator and subsequently a relatively heavy flight object, and the other providing for a ground based generator, wherein the energy extracted from the wind has to be mechanically transferred to the ground.
An example of the latter approach is the so-called pumping kite concept. A kite flies downwind of a ground-based generator connected to its steering lines, thereby pulling the lines and driving the generator as the kite departs from the generator. In order to recover the lines, the generator is driven as a motor to pull back the kite. During this phase, the kite is steered to exert less pull on the lines, so that power consumption for pulling back the kite is less than the power produced by the kite pulling the lines before.
The underlying problem of the invention is to provide for electric power production from wind using an airborne airfoil, wherein in particular the integrated energy yield is to be improved with respect to the prior art described above.